Happy Wednesday and welcome toOvernight Defense. I'm Rebecca Kheel, and here's your nightly guide to the latest developments at the Pentagon, on Capitol Hill and beyond.

THE TOPLINE: Ronny Jackson's nomination to be Veterans Affairs secretary appears to be in even worse shape than yesterday as allegations of wrongdoing pile up.

On Wednesday afternoon, Senate Veterans Affairs Committee Democrats released a compilation of the allegation against Jackson.

The revelations in the document include that he has been accused of providing a "large supply" of Percocet to a White House Military Office staffer. The missing medication had sent the White House Medical Unit "into a panic," according to the report.

Jackson was also accused of getting drunk and wrecking a government vehicle at a Secret Service going away party, the report says.

Jackson's defense: Jackson denied the allegations he drunkenly wrecked a car and said his embattled nomination is "moving ahead."

"I never wrecked a car," Jackson told reporters at the White House, adding that he has "no idea where that is coming from."

Jackson said the charge would be easy to disprove and insisted "we're still moving ahead as planned."

White House digs in: The White House showed no signs Wednesday of abandoning Jackson.

"He has received more vetting than most nominees," she told reporters at a daily briefing dominated by questions about Jackson, whose nomination appeared to be on life support after the allegations of misconduct.

Sanders said Jackson had been scrutinized in a "pretty thorough vetting process done by the FBI, as well as three independent investigations."

Takeaway: It's hard to see how Jackson survives the growing firestorm around his nomination.

Senators were already skeptical of Jackson's lack of experience managing a bureaucracy as large as the VA. And veterans service organizations, which have considerable sway on veterans issues in Congress, are getting increasingly frustrated at the dysfunction over VA leadership.

What is means: Pompeo will be in place ahead of a number of thorny foreign policy debates, including Trump's May 12 deadline to decide whether to withdraw from the Iran deal and the upcoming summit with North Korean leader Kim Jong Un that Trump has said will take place in May or June.

NDAA GETS GOING: National Defense Authorization Act (NDAA) season officially kicked off Wednesday, as subcommittees release their portions of the bill and committee staffers briefed reporters.

The most juicy details won't be known until the so-called "chairman's mark" is released in the coming weeks, but the subcommittees offered a few interesting tidbits.

Here's a rundown of what we learned Wednesday:

Space: Lawmakers on a House panel are moving forward with a push to build up a space war fighting unit, though they are stopping short of trying to create a separate military branch as floated by President Trump.

The House Armed Services Strategic Forces Subcommittee is working to use its portion of the annual defense policy bill to create a new numbered unit within the Air Force as well as a subunified command that would report to Strategic Command.

"I don't think that the members are backing off on this," a committee staffer said of the so-called space corps suggested by some Republicans in recent months.

"President Trump has come out and said that he has endorsed an independent space force. I think our members are still focused on that. I think our members also realize that nothing happens overnight," the staffer said.

Oxygen issues: A subcommittee of the House Armed Services Committee is taking steps in its portion of the annual defense policy bill to address physiological episodes that have been hitting military pilots midflight, committee staffers said Wednesday.

"This mark reflects the continued emphasis on keeping this issue in the spotlight at senior department-level leadership so we can continue to work this," a staffer told reporters at a background briefing.

Navy and Air Force pilots on various aircraft have been reporting unexplained incidents of hypoxia, which is when the body is deprived of oxygen at the tissue level.

There have also been unexplained incidents of disorientation, and hypocapnia and hypercapnia, which is when there is abnormally low and high levels, respectively, of carbon dioxide in the blood.

Navy ships: House lawmakers are proposing giving the Navy three more ships than it asked for in fiscal 2019 -- one aircraft carrier and two littoral combat ships.

A House Armed Services Committee's subpanel would give the Navy a total of 13 ships in its portion of the National Defense Authorization Act (NDAA).

Pay, troop bump: The House Armed Services Committee is supporting a White House push for a 2.6 percent pay raise for troops in fiscal year 2019, according to a draft defense policy bill released Wednesday.

The committee's military personnel subpanel – in its mark for the FY-19 National Defense Authorization Act – wants "full funding of the by-law pay raise for the troops, the highest in 9 years," a notice of the mark states.

Unlike last year, the pay increase is in line with what the White House asked for in President Trump's budget proposal released in February.